CN1150593A - Apparatus and method for removing residual monomers - Google Patents
Apparatus and method for removing residual monomers Download PDFInfo
- Publication number
- CN1150593A CN1150593A CN96112280A CN96112280A CN1150593A CN 1150593 A CN1150593 A CN 1150593A CN 96112280 A CN96112280 A CN 96112280A CN 96112280 A CN96112280 A CN 96112280A CN 1150593 A CN1150593 A CN 1150593A
- Authority
- CN
- China
- Prior art keywords
- slurries
- pvc
- column plate
- chamber
- residual monomer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F6/00—Post-polymerisation treatments
- C08F6/06—Treatment of polymer solutions
- C08F6/10—Removal of volatile materials, e.g. solvents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/08—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with moving particles
- B01J8/12—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with moving particles moved by gravity in a downward flow
- B01J8/125—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with moving particles moved by gravity in a downward flow with multiple sections one above the other separated by distribution aids, e.g. reaction and regeneration sections
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
- B01D3/14—Fractional distillation or use of a fractionation or rectification column
- B01D3/16—Fractionating columns in which vapour bubbles through liquid
- B01D3/22—Fractionating columns in which vapour bubbles through liquid with horizontal sieve plates or grids; Construction of sieve plates or grids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
- B01D3/34—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping with one or more auxiliary substances
- B01D3/38—Steam distillation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F6/00—Post-polymerisation treatments
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F6/00—Post-polymerisation treatments
- C08F6/001—Removal of residual monomers by physical means
- C08F6/003—Removal of residual monomers by physical means from polymer solutions, suspensions, dispersions or emulsions without recovery of the polymer therefrom
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S159/00—Concentrating evaporators
- Y10S159/10—Organic
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S203/00—Distillation: processes, separatory
- Y10S203/09—Plural feed
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Dispersion Chemistry (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
Abstract
Disclosed are equipment and method to remove residual monomers; wherein optimum treatment conditions can be selected flexibly for different types of PVC; in addition, the liquidity of the PVC slurry in the equipment can be well maintained to produce high-quality PVC stably and the operation can be controlled to maintain high efficiency and stability. The equipment comprises a hollow cylindrical tower (4); tower plates (31-37), each provided with a plurality of openings (43); chambers (8, 25-31); slurry inlets (19-24); downlink areas (13-18); a steam inlet 10; a slurry outlet (12); and hot water injectors (46-51). The diameter of the tower plate of the chamber (26) with a slurry inlet is 1.05-5 times that of the tower plate of the chambers 25 and 27.
Description
The present invention relates to a kind of equipment that is used to remove unreacted residual monomer, described monomer mainly comprises the vinyl chloride monomer produced in the mixture that is included in polyvinyl chloride (below be called PVC) and water-bearing media (below be called the PVC slurries) in the vinyl chloride resin (below be called PVC) (below be called VC).The invention still further relates to the method for removing unreacted residual monomer with this equipment.
More specifically, the present invention relates to a kind of applied widely being used to and remove the equipment of residual monomer, so that a kind of equipment that is used to remove residual monomer can be obtained same high processing efficiency for PVC performance or character and the widely different PVC slurries of the monomeric easiness of release, thereby produces high-quality resin under good processing property.The invention still further relates to the method for removing residual monomer with this equipment.
PVC is the resin that excellent chemical and physicals are arranged, and therefore, it is used for a lot of fields.Usually, PVC is by suspension polymerization, and letex polymerization or mass polymerization prepare.In these methods, suspension polymerization and letex polymerization are more commonly used, because they have the following advantages: reaction heat is easy to remove, and can produce less PVC finished product of foreign matter content and the PVC after the polymerization and are granular and do not need granulation step.General such the carrying out of suspension polymerization and letex polymerization: VC, water-bearing media, dispersion agent, polymerization starter etc. are put into the reactor that agitator is housed, make it remain on polymerization VC under the predetermined temperature.
In fact polyreaction does not change into PVC with generally not lasting till VC100%, but when transformation efficiency is 80-95% termination reaction, so that Optimal Production efficient to be provided.Therefore, the PVC slurries after polyreaction stops contain a considerable amount of unreacted residual monomers.
Because these residual monomers are harmful, thus must be noted that prevent residual monomer sneak into the PVC particle be transferred to waste water or air in.Therefore, must from the PVC slurries, remove and reclaim residual monomer as much as possible.
According to traditional method of removing residual monomer, be that water medium is mechanically separated with polymerization gained PVC slurries, remove less water medium and the residual monomer that is contained among the PVC by warm air-drying etc. then, obtain PVC powder as finished product.These methods can not be removed residual monomer effectively from waste water, in addition, residual monomer is sneaked into by in the moisture eliminator expellant gas.And, residual monomer is removed to enough levels from finished product PVC powder.Therefore, traditional method is not satisfied with regard to safety, health and environment protection.
As the method for removing and reclaim unreacted residual monomer the slurries after stopping polymerization effectively, Japanese Patent Application Publication JP54-8693 and 56-22305 have proposed a kind of method, its used equipment comprises a hollow circle tube tower, many column plates that some perforation are arranged are arranged in the tower, be placed in the tower at certain intervals each other, have an opening to be used for to the tower injecting steam at the bottom of the tower, cat head has a slurries inlet and a venting port.In this equipment, handle the PVC slurries like this: at first, add slurries from unique PVC slurries inlet at the top basically that is arranged on hollow circle tube equipment.The PVC slurries flow along the processing path that forms on the column plate, and some perforation are arranged on the column plate, substantially concentric layout, and partition wall is arranged on the plate to form many U type bending process paths.When slurry stream was crossed this path, it was exposed to by the hole on the column plate from the steam that upwards spray the bottom.Therefore, when slurries flow down column plate singly, be contained in the residual monomer gasification in the slurries and separate.Discharge by the unique PVC slurries discharge outlet that is arranged on device bottom basically through the PVC slurries of handling like this.
At present, because the application variation of PVC, the quality aspect of PVC has obtained various improvement.As a result, remove the problem variation of residual monomer, meet degraded and the bubbling of slurries in separating the equipment of residual monomer when hot but described problem relates to release property, the PVC of the residual monomer that depends on PVC granule interior structure.Especially, be improved to particle mesoporosity amount and contained the residual monomer of staying after a large amount of polyreactions in the PVC particle to increase PVC with absorbed plasticising dosage greatly.Therefore, if comprise the PVC slurries of this kind PVC with traditional device processes of removing residual monomer, when slurries contacted with steam, the residual monomer of gasification made slurries bubbling exceedingly, produces following shortcoming:
1.PVC slurry stream is crossed division plate, discharges without predetermined processing path.Therefore, do not remove the PVC slurries of residual monomer fully and sneak in the PVC slurries that normally pass through path, contain the PVC particle contamination PVC finished product of high density residual monomer.
2. the PVC particle that is blown afloat by bubble is tending towards being attached on the equipment inwall.The particle that adheres at high temperature is exposed to the steam mesometamorphism for a long time and produces coloured particle, and it is sneaked in the PVC finished product, reduces its value.
By reducing the add-on of PVC slurries in traditional method, so that slurries do not flow through partition wall, can overcome these defectives.Yet this method causes per hour handling in the residual monomer treatment process reduction of PVC amount, thereby reduces the amount of per hour producing the PVC finished product.
Be easy to discharge under the situation of residual monomer at PVC, the PVC required time that the duration of contact of PVC and steam, comparable residual monomer was difficult to therefrom remove is short.But, if remove the condition that the equipment design of residual monomer becomes to satisfy to be suitable for handling the PVC slurries that residual monomer is difficult to therefrom remove, then the PVC slurries that are easy to discharge with this kind device processes residual monomer will produce such undesired result, and promptly PVC the over-drastic thermal destruction takes place and destroys the quality of PVC finished product.This is because the PVC slurries have contacted unwanted time expand with steam after residual monomer is fully removed.On the other hand, be designed to satisfy the condition that is suitable for handling the PVC slurries that residual monomer is easy to therefrom remove if remove the equipment of residual monomer, if and the PVC slurries that are difficult to therefrom remove with this device processes residual monomer, then residual monomer can not be removed fully, makes the PVC slurries remove the residual monomer that still contains high density after the process through residual monomer.Therefore, traditional equipment of removing residual monomer can not satisfy the situation that PVC slurries to be processed contain the PVC that residual monomer is easy to therefrom remove, and can not satisfy the situation that PVC slurries to be processed contain the PVC that residual monomer is difficult to therefrom remove.
For addressing the above problem, the inventor has carried out diligent research, and the result develops and can meet the equipment that is used to remove residual monomer that the different various PVC slurries of feature require, and the method for this equipment of use, has finished the present invention.
More specifically, study, find following true by the bubbling of PVC slurries when removing residual monomer.At first, the bubble that the PVC slurries produce during with steam treatment on column plate is to be produced by residual monomer and water medium that the PVC granule interior discharges.Secondly, bubbling makes that the overflow of mobile PVC slurries surpasses the partition wall of dividing treatment channel on the column plate.The 3rd, slurries contact 5 minutes with steam, are present in the intragranular residual monomer of PVC and have removed and be no less than 70%, suppose that thus it is on the column plate of the bottom of the chamber of at first introducing as the PVC slurries that the bubbling phenomenon takes place the most violent.By these facts, find: when increasing as the column plate diameter of the bottom of the chamber that at least one PVC slurries inlet is arranged so that during greater than the diameter of other column plate, the highly significant of PVC slurries reduces on the column plate, thereby, the bubble overflow that prevents the bubbling slurries surpasses partition wall, according to this method, needn't reduce PVC slurries amount to be processed.In addition, to be tending towards boiling more violent in view of containing PVC slurries that residual monomer is easy to therefrom remove, so following carrying out.At first, PVC slurries inlet is set at least two chambers that separate of tower.Then, when processing need time expand with evaporation when separating the PVC slurries of VC, add slurries with the assurance residence time by the slurries inlet in chamber far away as far as possible, the chamber of band slurries outlet.On the other hand, when handling VC at short notice therefrom when gasification and isolating PVC slurries, can provide necessary being enough to gasify and the residence time of separating VC by adding slurries by the slurries inlet near relatively chamber, the chamber of band slurries outlet, avoid PVC slurries and steam long duration of contact simultaneously, thereby do not cause the undue thermal destruction of PVC.
Term used herein " porosity " means the volume (milliliter/gram) of micropore among the PVC.
Claimed invention is summarized as follows among the application:
One hollow circle tube tower;
Somely be placed on column plate in the tower at each interval at vertical direction, each column plate has many perforation;
Several chambers, each chamber forms on as one of column plate of the bottom of this chamber;
The slurries inlet that at least two chambers, is provided with;
A descender that is provided with between two adjacent column plates is so that slurries flow to the column plate of low chamber in succession downwards from the column plate of higher chamber;
A steam-in that at the bottom of tower, is provided with; With
The slurries outlet that in than a low chamber of the chamber that the slurries inlet is arranged, is provided with,
Wherein there is column plate diameter in one of the chamber of slurries inlets to be respectively this 1.05-5 that column plate diameter in each chamber up and down of column plate of chamber of slurries inlet arranged of next-door neighbour doubly.
In another aspect of this invention, provide a kind of equipment as mentioned above, also comprise the hot water jet device, this device is positioned near at least one column plate, in the face of the bottom surface of this column plate.
Preferably, the diameter in each hole is the 0.5-5.0 millimeter.
Preferably, the ratio of perforated area and column plate area is 0.001-10% in each column plate.
In another aspect of this invention, provide a kind of method of removing residual monomer with aforesaid device, this method may further comprise the steps:
Add the slurries that contain polyvinyl chloride by the slurries inlet;
Be blown into steam by the steam-in that is positioned at the bottom of the tower;
When slurries are downward through column plate, slurries are contacted with steam;
Thereby from slurries, separate residual monomer; With when tower top discharge goes out to contain the gas of the residual monomer of telling, the slurries of therefrom removing from slurries outlet discharging residual monomer;
Wherein the step that imports the slurries that contain polyvinyl chloride is undertaken by following (1), (2) or (3):
(1) under the situation that residual monomer is difficult to remove from slurries, add slurries by entering the mouth with the slurries that are provided with in the chamber on the chamber of larger-diameter column plate,
(2) under the situation that residual monomer is easy to remove from slurries, add slurries by the slurries inlet that is provided with in the chamber of band than the major diameter column plate, or add slurries than the slurries inlet that is provided with in the chamber under the chamber of major diameter column plate by band,
(3) have under the situation of high bubbling at slurries, add slurries by the slurries inlet that is provided with in the chamber with larger-diameter column plate.
Especially, when the porosity of polyvinyl chloride in the slurries is not less than 0.300 milliliter/gram, adds slurries in the chamber that larger-diameter column plate is arranged or be arranged in chamber under this chamber.
And when the porosity of polyvinyl chloride in the slurries is not less than 0.350 milliliter/gram, the slurries adding is had in the chamber of larger-diameter column plate.
When the porosity of polyvinyl chloride in the slurries during, slurries are added the chamber that is arranged on the chamber that larger-diameter column plate is arranged less than 0.300 milliliter/gram.
Fig. 1 uses the present invention to remove residual monomer equipment for expression and removes the synoptic diagram of the method for residual monomer;
Fig. 2 is the floor map of perforate column plate; With
Fig. 3 is the vertical synoptic diagram of perforate column plate.
The equipment of removing residual monomer of the present invention can be selected optimum condition according to each PVC to be processed, thereby when processing the PVC slurries that residual monomer is difficult to therefrom remove, prolong the time of staying, opposite, when processing the PVC slurries that residual monomer is easy to therefrom remove, reduce the time of staying. Therefore, basically do not need to change according to the difficulty or ease that discharge residual monomer the amount of processed PVC slurries. Thereby available present device is removed residual monomer very effectively.
In addition, according to the present invention, controlled condition and the PVC that various different qualities and performance are arranged that is used for can not processing single legacy equipment removes residual monomer neatly. For example, according to the bubbling of slurries, the difficulty or ease that discharge monomer and the PVC susceptibility to thermal degradation, an available equipment is removed residual monomer effectively.
In the present invention, term PVC be used in reference to VC homopolymers, VC and can with copolymer, the polymer of VC glycerol polymerization gained on olefin polymer and the polymer that is formed by two or more these polymer of the monomer of VC polymerization. In order effectively to remove residual monomer according to the present invention, polymer preferably contains 50% (weight) or more VC as the construction unit of polymer. This polymer can be obtained by suspension polymerisation or emulsion polymerisation.
The carboxylate that can comprise with the instantiation of the monomer of VC polymerization vinyl alcohol is such as vinyl acetate; Vinyl ethers such as alkyl vinyl ether; Esters of unsaturated carboxylic acids such as acrylate and methacrylate; Ethenylidene halogen such as vinylidene chloride and vinylidene fluoride; Unsaturated nitrile such as acrylonitrile; With alkene such as ethene and propylene.
In the present invention, term PVC slurries are used in reference to the slurries that contain PVC and aqueous medium. The PVC slurries also contained unreacted residual monomer after polymerisation stopped except containing PVC and aqueous medium. During PVC produces, use dispersant such as polyvinyl alcohol and hydroxypropyl methylcellulose, use the particle size conditioning agent of buffer, PVC, the reagent that suppresses sticking dirt, defoaming agent etc. when needing. Thereby the PVC slurries can contain these additives of requirement.
Concentration (hereinafter referred to as concentration of slurry) with contained PVC in the PVC slurries of the inventive method processing is preferably 5-45% (weight), more preferably 10-40% (weight). If concentration of slurry is too high, then the PVC slurries are except the mobile variation in the residual monomer equipment. On the other hand, if concentration of slurry is too low, the PVC actual amount of then processing significantly reduces.
Generally speaking, can be after polymerisation has stopped and the interior pressure of reactor is sent into the slurries of PVC serum pot before or after being down to atmospheric pressure through the PVC slurries that the present invention processes. Perhaps, also can use and send into after the PVC serum pot in polymerization process the PVC slurries of termination polymerisation when conversion ratio reaches any point. With predetermined flow velocity the PVC slurries are delivered to the residual monomer equipment of removing of the present invention by serum pot with conveyer such as pump.
The method of removing residual monomer in the PVC slurries with equipment of the present invention is described below with reference to Fig. 1-3. But the invention is not restricted to specific embodiment described herein.
Fig. 1 is the schematic diagram of removing residual monomer equipment according to implementation of the present invention. This equipment comprises hollow circle tube tower 4, be arranged on some column plate 31-37 in the tower 4 at vertical direction, each column plate has many perforates, upper some chambers 8 and the 25-30 that forms of one of each leisure column plate 31-37 at the bottom of as the chamber, the slurries entrance 19-24 that at least two chambers, arranges, descender 13-18 between two adjacent column plates, this district makes slurries in succession flow to the column plate of low chamber downwards from the column plate of higher chamber, steam inlet 10 in tower 4 bottoms, than the slurries outlet 12 in the low chamber, the chamber 29 that the slurries entrance is arranged be close to separately hot water jet device 46-51 under the column plate 31-36. There is the diameter of the column plate of one of chamber of slurries entrance-chamber 26 to be the 1.05-5 times of column plate diameter in the next- door neighbour chamber 25 and 27 of chamber 26 about. In the chamber, top 8 of tower 4, be provided with degassed mouthful 11 that links to each other with condenser 7. Column plate 31-37 all has many perforates 43 as shown in Figure 2. On each column plate, partition wall 38-42 is all arranged so that the slurries that flow downward form many U-shaped bending channels that limited by partition wall and inner wall of tower (or zigzag passage). Numeral 45 expression demarcation strips. Slurries entrance 19-24 links to each other with the slurries supply line that valve 19A-24A is arranged. The slurries supply line also links to each other with serum pot 1 through valve 52,53, heat exchanger 3 and pump 2.
Equipment of the present invention can easily be made as the column plate chamber (between cutting apart) that column plate 31-37 is arranged of unit by assembling. Perhaps, if the repacking legacy equipment, could be by would replacing the column plate manufacturing of legacy equipment with the larger-diameter column plate 33 that has of making separately in advance.
In equipment shown in Figure 1, will add heat exchanger 3 by suspension polymerisation or emulsion polymerisation gained and the PVC slurries that temporarily are stored in the PVC serum pot 1 by pump 2. In heat exchanger 3, slurries are heated to predetermined temperature, then by arbitrary PVC slurries entrance 19-24 with in the slurries adding equipment.
The flow velocity that adds the PVC slurries in the tower body 4 of removing residual monomer equipment is area 0.1-300 cube m/h of every square metre of column plate 31 shown in Figure 2, preferred 1-100 cube m/h. Preferably regulate flow velocity by the amount of liquid that is advanced by pump 2.
Preferably at the 50-100 ℃ of PVC slurries that will add tower 4 with heat exchanger 3 preheatings. During the preheating slurries, the efficient of removing residual monomer increases.
The internal diameter of column plate in the tower 4, to the column plate of minimum diameter, its internal diameter is the 200-10000 millimeter; For the column plate of maximum inner diameter, its internal diameter is 5 times of the 1.05-that the column plate internal diameter of minimum diameter is arranged, and preferred 1.2-5 doubly.
Each own column plate can be same to each other or different to each other in being parallel to arbitrary section of column plate as the inner rim shape and size of the chamber of its bottom.
The height of tower 4 be have minimum diameter the column plate diameter 2-20 doubly, more preferably 5-15 is doubly.
The residual monomer equipment of removing according to the present invention has the slurries entrance at least 2 chambers. In addition, as the column plate diameter at the bottom of the chamber that the slurries entrance is arranged be generally the next-door neighbour have the slurries entrance the chamber column plate up and down in each chamber the 1.05-5 of column plate diameter doubly, preferred 1.2-5 is doubly.
The difficulty or ease of PVC slurries release monomer depend on the structure of PVC particle in the PVC slurries. When the PVC particle has than macrovoid, contacting between PVC particle and the steam. Therefore, residual monomer is tending towards removing easily. In addition, the slurries that contain this PVC particle after the polymerization are tending towards bubbling. On the other hand, there is the PVC of smaller aperture to be difficult for discharging residual monomer. Therefore, in the present invention, when the porosity of polyvinyl chloride particles in the slurries is not less than 0.300 milliliter/gram, preferably adds slurries in the chamber that the larger diameter column plate is arranged or be arranged in chamber under this chamber. When the porosity of polyvinyl chloride particles in the slurries is not less than 0.350 milliliter/gram, preferably slurries are added in the chamber on the chamber that the larger diameter column plate is arranged. In addition, when the porosity of polyvinyl chloride particles in the slurries during less than 0.300 milliliter/gram, preferably slurries are added the chamber that is arranged on the chamber that the larger diameter column plate is arranged.
In removing residual monomer equipment, the number of plates be determine the PVC slurries in equipment the time of staying-be the decisive factor of the time of contact of PVC slurries and steam. In equipment of the present invention, determine like this number of plates, so that can guarantee in various PVC slurries to be processed that the PVC slurries that need maximum duration to discharge residual monomer have makes in the slurries residual monomer remove the necessary time of staying fully at least. The actual entrance that adds the PVC slurries can discharge the difficulty or ease of monomer and required time of staying selection according to slurries.
The time of staying in equipment can based on slurries discharge the difficulty or ease of monomer and the PVC slurries that will add in the PVC slurries of the concentration of residual monomer and discharge the predetermined concentration etc. of contained residual monomer determine.
The method that discharges the difficulty or ease control time of staying of monomer according to slurries is described below with reference to Fig. 1. For example, when processing the PVC slurries that are difficult for the release residual monomer, add the PVC slurries from slurries entrance 19. The PVC slurries that add flow into descender 13 by the treatment channel that the inwall by the partition wall 38-42 on column plate 31, the column plate 31 and tower forms, and flow to then on the column plate 32 of next adjacent chamber.
So join slurries on the column plate 32 in succession by the treatment channel on the column plate 32, flow to downwards again on the column plate in the following chamber. Thereby slurries finally are disposed to outside the equipment by PVC slurries outlet 12 by the treatment channel on the column plate 31-37. On the other hand, when the PVC slurries of residual monomer are easily removed in processing, for example, from PVC entrance 23 the PVC slurries are imported on the column plate 35.
Allow slurries process this slurries by the treatment channel on column plate 36 and 37 successively. In addition, when processing the PVC slurries of violent bubbling, for example, the PVC entrance 21 from column plate 33 chamber 26 adds the PVC slurries, and process in aforesaid mode, the diameter of column plate is bigger than the diameter that is close to respectively on this column plate column plate 32 in the chamber of chamber about in the of 26 and 34 in the chamber 26. Thereby, by select to add the column plate position of PVC slurries according to the characteristic of P VC slurries to be processed, can control the time of contact of PVC slurries and steam to removing the essential and time enough of residual monomer institute, can avoid PVC because contact excessively thermal degradation with steam. When processing the PVC slurries of easy bubbling, preferably the P VC entrance from chamber 26 21 adds slurries, chamber 26 be the column plate diameter take diameter as the diameter minimum 1.05-5 doubly, preferred 1.2-5 column plate 33 doubly is its end. If the diameter of column plate is big, the degree of depth of the P VC slurries of the column plate upper channel of then flowing through shoals. Therefore, steam reduced by the time of staying of PVC slurries on the column plate, can suppress column plate sizing liquor bubbling. Thereby, prevent that the PVC slurries that the overflow of PVC slurries surpasses partition wall and avoids residual monomer fully not remove from sneaking into the PVC product. In addition, the removal of possible stable residual monomer and the operation of equipment. If the diameter of column plate is less than 1.05 times of the column plate diameter of diameter minimum, the effect that then suppresses bubbling is limited. On the other hand, if the diameter of column plate greater than 5 times of the column plate diameter of diameter minimum, then per unit area is not enough to stir the PVC slurries very little by the quantity of steam that the hole is blown into the column plate chamber. This will cause the PVC solids precipitation, sometimes make the operation difficult of equipment. In addition, the constructions cost of equipment will be increased.
The difficulty or ease of PVC slurries release residual monomer depend on the porosity of PVC in the slurries. Therefore, can select to add based on the determined value of PVC porosity the mouth of slurries. That is, be not less than in porosity in the situation of 0.300 milliliter/gram, the arbitrary chamber 28 under being arranged in chamber 26 (the bigger column plate of diameter is arranged) or chamber 26,29 and 30 slurries entrance add slurries. Porosity be not less than 0.350 milliliter/gram or slurries tend in the situation of bubbling, slurries are added in 26 (the bigger column plate of diameter is arranged) of entering the room. In addition, in the situation of porosity less than 0.300 milliliter/gram, slurries are added the chamber 25 that is arranged on the chamber 26.
Although in equipment shown in Figure 1, only provide a slurries outlet 12, some slurries outlets can be provided in any chamber under slurries add entrance. If some slurries outlets are provided, then might select to discharge the outlet of slurries. Therefore, especially restriction remove in the equipment of residual monomer the residing chamber of larger diameter column plate arranged. This is because can be by selecting the control of export time of staying.
When finishing the demonomerization processing, if the temperature height of PVC slurries, the efficient of then removing residual monomer increases. Yet, if temperature is too high, causes the painted or thermal degradation of PVC particle and go bad. Therefore, must suitably regulate the temperature of PVC slurries.
Temperature at the mobile slurries of column plate is generally 50-150 ℃, and preferred 70-120 ℃, more preferably 80-110 ℃. The temperature of PVC slurries can be by temperature and the amount control by the steam that sprays into below on the column plate.
Pressure in the tower 4 preferably remains on 0.2-3 kilogram/square centimeter (absolute pressure).
Temperature and pressure is because of the interference overbalance in the residual monomer equipment if remove, and then mobile being tending towards of PVC slurries fluctuates on the column plate.With regard to its reason, can mention that the main fluctuation because of the PVC slurries amount of being discharged from the outlet of PVC slurries of the heat that exchanged by interchanger changes, so from the temperature change of the PVC slurries of PVC slurries inlet adding.In the case, if all column plates have identical size, then the fluctuation that is produced causes fluctuation of service to next column plate transmission.On the contrary, with the residual monomer equipment of removing of the present invention, in the time of in the PVC slurries add than the big column plate of other column plate diameter, the processing of removing residual monomer begins to carry out under than the little mild conditions of other column plate at the quantity of steam that sprays into.Thereby the surge movement that has begun relaxes having on the larger-diameter column plate, to cut off the transmission of surge movement to following column plate.In addition, with the residual monomer equipment of removing of the present invention, PVC slurries mobile highly stable.Thereby, even the output of PVC slurries is also stable.Therefore, equipment of the present invention is having surprising effect aspect the reason of solution or reduction generation fluctuation itself significantly.
In the processing of removing residual monomer, even be difficult for to discharge, or in other words, need a lot of column plates in the above in the mobile PVC slurries, also needn't during entire treatment, suppress the bubbling of slurries for slurries at residual monomer.Particularly when in the equipment of removing residual monomer during the temperature and pressure overbalance, bubbling makes the operation of equipment become unstable sometimes.If all column plates have same size, then bubbling is held and is continued to following many column plates, and the PVC particle that is lifted by bubble or foam is tending towards sticking on the locular wall.Thereby, even when removing on the wall adherent PVC with water spray, isolated PVC sneaks among the PVC that emits from the equipment of removing residual monomer as colored particle sometimes.With the residual monomer equipment of removing of the present invention, any bubbling is no matter its degree how, all can have mitigation effectively on the larger-diameter column plate.Therefore, when handling not significantly boiling with present device and usually being difficult to discharge the PVC slurries of residual monomer, in by the process of this column plate, eliminate bubbling basically.Thereby, seldom find colored PVC among the PVC that discharges in the slave unit.
The equipment of removing residual monomer of the present invention, based on its aforesaid special construction and shape, thereby might produce fabulous effect aspect contained coloured PVC particulate amount among the treated PVC of control in stable operation under the high level with under high and stable level in the fluctuation that relaxes the PVC slurries, this effect never obtained with legacy equipment.
For handling not bubbling or the only slurries of slight bubbling, the column plate that slurries add on it preferably has less diameter.If diameter reduces, the quantity of steam that the per unit area column plate sprays increases.In addition, the degree of depth of column plate sizing liquor deepens.Thereby can guarantee on column plate is enough to increase the efficient of removing residual monomer the duration of contact of PVC slurries and steam.Because along with slurries flow down the density loss of residual monomer in the PVC slurries by the descender in the equipment, so, though the degree of depth of following column plate sizing liquor deepen, below bubbling on the column plate still do not have on the top tray violent.
With reference to figure 1, the PVC slurries that high bubbling arranged enter the mouth by slurries in the 21 adding equipment.So the PVC slurry stream that adds is crossed the treatment channel that is formed by partition wall on the column plate 33 of some perforation.Slurries flow to next column plate downwards through descender 15.In the case, although the slurries amount that adds on the column plate 33 is identical with other column plate,, can reduce the slurries amount that per unit area column plate 33 adds equipment because the diameter of column plate 33 is big.Thereby, promptly use the PVC slurries of violent bubbling, still can when suppressing bubbling, finish demonomerization effectively and handle.
In this specification sheets, remove each having some perforation and on one surface, having the column plate of a plurality of vertical partition walls to be called " tower plate structure " in the residual monomer equipment.
Perforate in the column plate is used for making the PVC slurries remove the processing of residual monomer via the steam that sprays into by perforate when slurries flow on column plate.Must set the amount of size, vapor pressure and the adding steam of each perforate, flow down by perforate not make the PVC slurries, perforate is not stopped up, by the steam that sprays into below continuously and equably by perforate.
The diameter in each hole is not more than 5 millimeters in the column plate, preferred 0.5-2 millimeter, more preferably 0.7-1.5 millimeter.The percentage of open area of each column plate (area of the total area/column plate of perforate) is 0.001-10%, preferred 0.04-4%, more preferably 0.2-2%.If percentage of open area is too little, then the PVC particle in the mobile PVC slurries is not enough to the steam that sprayed into by perforate and stirs on column plate, causes the PVC solids precipitation and reduces the efficient of removing residual monomer.In addition, the flowability of PVC slurries also reduces.On the other hand, if percentage of open area is too high, the phenomenon that the PVC slurries drip from perforate (this phenomenon hereinafter is called slurries and leaks) taking place then, or wastes a large amount of steam and leak from perforate to prevent slurries.
Partition wall is used to guarantee that the PVC slurries can pass through its mobile treatment channel on column plate.Owing to there is a partition wall, with the steam treatment slurries with the process of removing residual monomer wherein in, the PVC slurries certain hour that can on each column plate, flow.Tower plate structure shown in Fig. 2 and 3 has partition wall 38-42, alternately is distributed on the column plate 31.
The residence time of PVC slurries in removing residual monomer equipment is the time of the treatment channel that forms on the column plate of PVC slurries by pre-determined quantity.Therefore, if require to add the PVC slurries of increasing amount when each column plate has fixed diameter, the height that then increases demarcation strip 45 gets final product, and demarcation strip is divided each treatment channel from inlet to each descender in equipment.By the height of control demarcation strip, can regulate the liquid depth of PVC slurries on the column plate.Limit treatment channel by the mode that partition wall is installed.The pattern of passage is preferably the hair clip curved shape shown in Fig. 2.The example selected of other type comprises scroll, wheel shape and star (radiation).
On the tower plate structure of the present invention, there be not special restriction aspect the quantity of partition wall and the width of channel.Yet if the quantity of partition wall excessively increases and the height of passage is too high, the liquid depth of PVC slurries is too dark, causes not preferred slurries liquid flooding to surpass partition wall.
Equipment of the present invention has steam-in 10 in the bottom compartment 9 of tower.10 steam that add blow on mobile PVC on these column plates by the perforate the column plate 37-31 from entering the mouth.The amount that adds steam be preferably 1 cubic metre of PVC slurries 1-100 kilogram/hour, more preferably the 5-50 kilogram/hour.If this amount is too little, the PVC solids precipitation in the PVC slurries then, thereby can not remove residual monomer in the PVC slurries effectively.On the other hand, if the quantity of steam that adds is too big, then the PVC slurries splash tempestuously, make the processing of removing residual monomer be difficult to stablize.In addition, and add a large amount of vapor phases, cause the processing efficiency of non-constant than not improving the efficient of from the PVC slurries, removing residual monomer.
There is at least one hot water jet device the preferred just in time position under column plate of present device.Hot water jet device 46-51 is processed into predetermined shape by the pipe that the plurality of nozzles hole will be arranged to form the nozzle manufacturing.Nozzle preferably is set like this, so that hot water is sprayed with the direction that vertical curve is 10-60 ° of angle in the edge.In the equipment of Fig. 1, hot water jet device 46-51 be placed on respectively column plate 31-36 under.Spray hot water by each device at interval with preset time, the lower surface of flushing column plate and the inwall of tower.
The shape that constitutes the pipe of hot water jet device 46-51 is generally shape, scroll, star or the hair clip shape that resembles omega or Φ.Also can adopt multi-layer annular, wherein ring is stacked so that all placements with one heart of other each ring.Each hot water jet device 46-51 is arranged in parallel and under each column plate.Yet if the outermost portion of hot water jet device 46-51 is too near apart from the inner peripheral wall of tower, the PVC particle that has flushed out and other material may stop up the gap.Therefore, preferred place the hot water jet device like this, so that the outermost portion of each device is apart from 20 millimeters of the inner wall surface of tower or more.
The shape of nozzle bore can be circle, ellipse, crack shape etc. among the hot water jet device 46-51.Select described shape according to application target.If adopt circularly or oval, diameter or main shaft generally are selected in the scope of 1-8 millimeter, and if adopt crack shape, then the maximum length in slit is generally in the scope of 1-8 millimeter.
The PVC slurries of therefrom removing residual monomer in removing residual monomer equipment fully add in the interchanger 3 by pump 5.
Slurries cool off in interchanger 3, temporarily are stored in the PVC serum pot 6 then.Subsequently, make the slurries dehydration, add then in the drying plant (not shown).Having experienced the adding method of the PVC slurries of removing the residual monomer processing and processing step subsequently has no particular limits.
The monomer gas of telling in removing residual monomer equipment can condensation in condenser 7 after gas is by degassing mouth 11.If water of condensation contains a large amount of vinyl chloride monomers, can handle described water of condensation again by it being returned remove residual monomer equipment.
Embodiment
Describe the present invention below with reference to embodiment and Comparative Examples, should not be construed as restriction the present invention.In the following Examples and Comparative Examples, the following evaluation.
(1) concentration of residual monomer:
After the PVC slurries are discharged from slurries outlets, take a sample immediately and dewater.With the Gas Chromatograph 9A (trade(brand)name) that ShimadzuCorporation produces, measure the concentration of residual chlorine vinyl monomer in the PVC particle based on " space on the liquid " method.Measure according to ASTM D4443.FID is adopted in the test section.
Usually, the concentration of residual chlorine vinyl monomer makes it be no more than 1ppm in the control PVC finished product.After slurries were discharged from remove equipment, the small portion of residual monomer can further be removed by subsequently step such as drying step.In PVC discharge stage from remove residual monomer equipment, the liquid degree of preferably controlling the residual chlorine vinyl monomer is to being not more than 10ppm.
(2) method of the mensuration flavescence factor (the thermal destruction factor):
Respectively remove residual monomer handle before and make the dehydration of PVC slurries afterwards.40 ℃ of dryings 24 hours.Then, under following rolling condition, preparation is by the following PVC plate of forming.Measure the flavescence factor of PVC plate according to JIS K7105.This value is big more, and flavescence (thermal destruction) factor is big more.
Form:
100 parts of PVC
Three generations (tri-basic) lead sulfate 3
Two generations (di-basic) lead sulfate 1
Calcium stearate 1
Stearic acid 0.5
Rolling condition:
8 inches rollers of roll type
170 ℃ of roller temperatures
0.32 millimeter of the thickness of rolled plate
Generally be known in the polymerization process, the more serious thermal destruction of PVC experience that the PVC that the polymerization degree is low is higher than the polymerization degree, because the PVC of front prepares under high relatively polymerization temperature at the PVC than the back, and the PVC of front contains a lot of unstable structures, and thermal destruction is from these unstable structures.Be also noted that the low PVC of the polymerization degree has less porosity, thereby residual monomer is difficult to from then on plant among the PVC separate.Therefore, the PVC that the polymerization degree is low must need the long slurries of the PVC higher than the polymerization degree and the duration of contact of steam when removing residual monomer.Owing to this reason, the PVC that the polymerization degree is low generally has the big flavescence factor of the PVC higher than the polymerization degree.In removing the method for residual monomer, be that the flavescence factor of 1300 PVC is not more than 5 and can to suppress the polymerization degree be that the flavescence factor of 700 PVC is not more than 10 if can suppress the polymerization degree, then the quality of finished product will not make its economic worth devalue.
(3) coloured PVC particulate quantity
Get the PVC slurries sample that a part is discharged from PVC slurries outlet 12.Dry this sample gets 100 gram polyvinyl chloride resins, is sprinkling upon on the white plotting paper.When mixing all sample resins with scraper, the coloured PVC particle of visual identification also picks.The coloured PVC particulate quantity of number.
(4) the bubbling condition on the column plate:
On the column plate of below two, representing, based on following judging criterion O﹠A bubbling condition with A and B.
Column plate A: as the column plate of the bottom of the chamber that slurries inlets is arranged, slurries are by in this adding equipment that enters the mouth from the outside.
Column plate B: the 3rd block of column plate (not including column plate A) under the above-mentioned column plate A.
Estimate:
A: only observe small bubbling or do not have bubbling.PVC slurries mobile fabulous.
B: low bubbling.The good fluidity of PVC slurries.
C: high bubbling, but the PVC slurries not overflow surpass partition wall.
D: steep overflow sometimes and surpass partition wall.
(5) porosity of PVC
Measuring method: mercury osmose process
Device: Porosimeter Model-70 (Carloelba manufacturing)
Pressure: maximum 2,000 kilograms/square centimeter
Average six measuring results.
Embodiment 1
(1) be used to remove the equipment of residual monomer:
The residual monomer equipment of removing used among the embodiment 1 has the structure shown in Fig. 1-3.Details is as follows:
A) stage number: 7
B) spacing between adjacent two column plates: 1,400 millimeter
C) detailed description of tower plate structure:
A) from descending the structure of several the 1st, 2,3,4,6 and 7 block of column plates:
Column plate diameter: 1,300 millimeter
The diameter in each hole: 1.3 millimeters
Percentage of open area (%): 0.3% (total area of perforate/column plate area)
Partition wall height: 500 millimeters
Interface wall height: 450 millimeters
The width of treatment channel: 200 millimeters
B) from descending the structure of several the 5th block of column plates:
Column plate diameter: 2,000 millimeters
The diameter in each hole: 1.3 millimeters
Percentage of open area (%): 0.3% (total area of perforate/column plate area)
Partition wall height: 290 millimeters
Interface wall height: 250 millimeters
The width of treatment channel: 200 millimeters
D) PVC slurries inlet:
Position: from following several Room the 3rd, 4,5,6,7 and 8.
Quantity: one of every chamber, totally 6 mouths.
E) PVC slurries outlet:
Position: from following several Room the 2nd.
Quantity: one.
F) hot water jet device:
Position: in 15 centimeters under each lower surface of following several the 2nd, 3,4,5,6 and 7 block of column plates.
Quantity: one of each position, totally 6 devices.
Diameter: 800 millimeters
Nozzle: round nozzle, 4 millimeters of each nozzle diameters.Some nozzle and vertical direction inclination 45 degree, other nozzle and vertical direction inclination 30 degree.
Arrange the lower surface of each nozzle with the inwall of washing chamber and next-door neighbour's top tray.
Shape: annular, by the pipe manufacturer of diameter 50A.
Spray regime: 10 minutes at interval, spray 5 seconds of hot water with 0.5 cubic metre/hour.
(2) used PVC slurries:
PVC: the homopolymer of mean polymerisation degree 1,300.
Concentration of slurry: 30% (weight)
The concentration of residual chlorine vinyl monomer: 30,000ppm
The porosity of PVC: 0.322 milliliter/gram
(3) 10 steam that add from the steam-in:
Temperature: 110 ℃
Flow velocity: 600 kilograms/hour
(4) remove the operation of residual monomer:
Stop rapidly the PVC slurries being sent into serum pot 1 with pump with 20 cubic metres/hour speed after the polyreaction, send into interchanger 3 again, be heated at these slurries.The slurries that heated from following several Room the 5th of removing residual monomer equipment-be that PVC slurries inlet 22 chamber 27 adds.Liquid flows through down that several the 4th, 3,2 and 1 block of column plates are the passage that the partition wall on column plate 34,35,36 and 37 is separated, therebetween with the aforesaid steam treatment slurries that spray by the perforate in each column plate with the release residual monomer.Mobile PVC slurries are steam heated to 100 ℃ on column plate, are flowed down by descender, remove outside the residual monomer equipment and be disposed to by PVC slurries outlet 12.Subsequently, carry the PVC slurries, in interchanger, be cooled to 50 ℃, be stored in the PVC serum pot 6 by pump 5.The vinyl chloride monomer of removing from the PVC slurries when slurries contact with steam on column plate is separated into vinyl chloride monomer and water of condensation in condenser 7, deliver to liquefied chlorine vinyl monomer step then to reclaim monomer.
The results are shown in the table 1.The concentration of residual chlorine vinyl monomer is 250ppb from the PVC that removes the discharge of residual monomer equipment, and the flavescence factor of the PVC product of moulding is 2.21, and coloured PVC granule number is 0.Equipment moves reposefully.Column plate A and B go up bubble and remain on low-level.Particularly on column plate B, almost do not observe bubbling, surprising good of the flow state of slurries.
Repeat the step of embodiment 1, but make following change on superincumbent condition (2) and (4).
(2) used PVC slurries:
PVC: the homopolymer of mean polymerisation degree 700.
Concentration of slurry: 30% (weight)
The concentration of residual chlorine vinyl monomer: 25,000ppm
The porosity of PVC: 0.231 milliliter/gram
(4) remove the residual monomer operation:
PVC slurries in following several Room the 8th of PVC slurries slave unit inlet 19 is added the residual monomer equipment of removing.
The results are shown in the table 1.The concentration of residual chlorine vinyl monomer is 350ppb from the PVC that removes the discharge of residual monomer equipment, and the flavescence factor of the PVC product of moulding is 8.62, and coloured PVC granule number is 0.Equipment moves reposefully.Column plate A and B go up bubble and remain on low-level.Particularly on column plate B, almost do not observe bubbling, surprising good of the flow state of slurries.
Repeat the step of embodiment 1, but make following change on superincumbent condition (2) and (4).
(2) used PVC slurries:
PVC: the homopolymer of mean polymerisation degree 1,300.
Concentration of slurry: 30% (weight)
The concentration of residual chlorine vinyl monomer: 30,000ppm
The porosity of PVC: 0.409 milliliter/gram
(4) remove the residual monomer operation:
PVC slurries in following several Room the 6th of PVC slurries slave unit inlet 21 is added the residual monomer equipment of removing.
The results are shown in the table 1.The concentration of residual chlorine vinyl monomer is 200ppb from the PVC that removes the discharge of residual monomer equipment, and the flavescence factor of the PVC product of moulding is 2.72, and coloured PVC granule number is 0.Equipment moves reposefully.Column plate A and B go up bubble and remain on low-level.Particularly on column plate B, almost do not observe bubbling, surprising good of the flow state of slurries.
Comparative Examples 1:
In Comparative Examples 1, with shown in Fig. 1-3 to remove residual monomer equipment opposite, use all column plates that the equipment of same size is all arranged, only have a slurries inlet and details as follows:
A) stage number: 7
B) spacing between adjacent two column plates: 1,400 millimeter
C) detailed description of tower plate structure:
A) structure of all column plates explanation:
Column plate diameter: 1,300 millimeter
The diameter in each hole: 1.3 millimeters
Percentage of open area (%): 0.3% (total area of perforate/column plate area)
Partition wall height: 500 millimeters
Interface wall height: 450 millimeters
The width of treatment channel: 200 millimeters
D) PVC slurries inlet:
Position: from following several Room the 8th.
Quantity: one.
E) PVC slurries outlet:
Position: from following several Room the 2nd.
Quantity: one.
F) hot water jet device:
Position: in 15 centimeters under each lower surface of following several the 2nd, 3,4,5,6 and 7 block of column plates.
Quantity: one of each position, totally 6 devices.
Diameter: 800 millimeters
Nozzle: round nozzle, 4 millimeters of each nozzle diameters.Some nozzle and vertical direction inclination 45 degree, other nozzle and vertical direction inclination 30 degree.
Arrange the lower surface of each nozzle with the inwall of washing chamber and next-door neighbour's top tray.
Shape: annular, by the pipe manufacturer of diameter 50A.
Spray regime: 10 minutes at interval, with 0.5 cubic metre/hour 5 seconds of amount injection hot water.
(2) used PVC slurries:
Use the slurries identical with embodiment 1.
(3) steam that adds from the steam-in that is arranged on the tower bottom compartment:
Temperature: 110 ℃
Flow velocity: 600 kilograms/hour
(4) remove the operation of residual monomer:
Repeat to remove the residual monomer step described in the embodiment 1, but the inlet of the PVC slurries in several Room the 8th adds the PVC slurries and removes in the residual monomer equipment under the slave unit.
The results are shown in the table 1.The concentration of residual chlorine vinyl monomer is 100ppb from the PVC that removes the discharge of residual monomer equipment, and the flavescence factor of the PVC product of moulding is 7.52.Because compare the duration of contact of slurries and steam with the embodiment 1 that handles identical PVC slurries long, the thermal destruction of moulding PVC product is big, thereby commercial value reduces.Column plate A goes up high-level bubbling.On column plate B, also observe bubbling.Coloured PVC granule number is 5.Use the hot water jet device although this numerical table shows, lifted by bubble and the PVC particle that adheres to the equipment inwall can not be removed by hot water fully.Think that the generation of coloured PVC is owing to bubbling.
Comparative Examples 2:
Repeat the step of Comparative Examples 1, but use the used PVC slurries of embodiment 2.
The results are shown in the table 1.High level ground bubbling slightly on the column plate A.On column plate B, also observe bubbling.Coloured PVC granule number is 4.Think that as in the Comparative Examples 1 the generation of coloured PVC is owing to bubbling.
Comparative Examples 3
Repeat the step of Comparative Examples 1, but use used PVC slurries among the embodiment 3.
The results are shown in the table 1.On column plate A, observe violent bubbling.The overflow of PVC slurries surpasses partition wall.It is unstable that the operation of equipment becomes.Since comprise the PVC slurries that some suitably do not contact with steam, so the concentration of contained residual chlorine vinyl monomer shows up to 80 among the PVC that discharges in the slave unit, the value of 000ppb.Discovery comprises 25 coloured PVC particles.Think that the PVC particle that is lifted by bubbling and adhere to the equipment inwall can not remove by injected fully water.On column plate B, though the height of bubbling descends slightly, the flow state of slurries is still unstable.
Comparative Examples 4
In Comparative Examples 4, used equipment stage number is lacked than the structure of removing residual monomer equipment shown in Fig. 1-3, and the diameter of going up column plate most is bigger than other column plate, a slurries inlet is only arranged in chamber, the top, and following detailed description is arranged:
A) stage number: 5
B) spacing between adjacent two column plates: 1,400 millimeter
C) detailed description of tower plate structure:
A) from following several the 1st, 2,3 and 4 tower plate structures:
Column plate diameter: 1,300 millimeter
The diameter in each hole: 1.3 millimeters
Percentage of open area (%): 0.3% (total area of perforate/column plate area)
Partition wall height: 500 millimeters
Interface wall height: 450 millimeters
The width of treatment channel: 200 millimeters
B) from descending the structure of several the 5th block of column plates:
Column plate diameter: 2,000 millimeters
The diameter in each hole: 1.3 millimeters
Percentage of open area (%): 0.3% (total area of perforate/column plate area)
Partition wall height: 290 millimeters
Interface wall height: 250 millimeters
The width of treatment channel: 200 millimeters
D) PVC slurries inlet:
Position: from following several Room the 6th.
Quantity: one.
E) PVC slurries outlet:
Position: from following several Room the 2nd.
Quantity: one.
F) hot water jet device:
Position: in 15 centimeters under each lower surface of following several the 2nd, 3,4 and 5 block of column plates.
Quantity: one of each position, totally 4 devices.
Diameter: 800 millimeters
Nozzle: round nozzle, 4 millimeters of each nozzle diameters.Some nozzle and vertical direction inclination 45 degree, other nozzle and vertical direction inclination 30 degree.
Arrange the lower surface of each nozzle with the inwall of washing chamber and next-door neighbour's top tray.
Shape: annular, by the pipe manufacturer of diameter 50A.
Spray regime: 10 minutes at interval, with 0.5 cubic metre/hour 5 seconds of amount injection hot water.
(2) used PVC slurries:
Use the slurries identical with embodiment 2.
(3) steam that adds from the steam-in of removing residual monomer equipment:
Temperature: 110 ℃
Flow velocity: 600 kilograms/hour
The results are shown in the table 1.The concentration of residual chlorine vinyl monomer is 80 from the PVC that removes the discharge of residual monomer equipment, 000ppb, and the flavescence factor of the PVC product of moulding is 2.98.Because the duration of contact of slurries and steam is inadequate, in other words, compare the processing power deficiency of equipment with the embodiment 2 that handles identical PVC slurries, so the concentration of residual monomer shows very high value among the PVC that discharges.The PVC polymkeric substance of the polymerization degree 700 is difficult to discharge residual monomer.Therefore, providing gentle treatment condition only can remove a spot of residual monomer with being used to alleviate on the larger-diameter column plate of having of bubbling.Thereby, the stage below under the situation that leaves the high density residual monomer, the PVC slurries being delivered to.As a result, the stage is below observed bubbling.Probably, comprise 6 coloured PVC particles owing to this reason.
According to the residual monomer equipment of removing of the present invention, can obtain following effect:
(1) because according to the present invention, can be flexibly and suitably select the condition of removing residual monomer, to meet the requirement of the feature PVC different with performance, thereby the thermal destruction degree of the bubbling of may command slurries, the difficulty or ease that discharge residual monomer, PVC and the operation efficiency of removing residual monomer equipment are to top condition generally.
(2) owing to can select treatment condition according to the characteristic of indivedual PVC after the polymerization, and compare with traditional method processing PVC slurries of removing residual monomer, do not destroy the proper property of PVC.
(3) can reduce colored PVC significantly.
(4) owing to relaxing and stable fluctuation and the bubbling that PVC slurries on the larger-diameter column plate are arranged, so unsettled slurry is not passed to following column plate.As a result, can highly flatly control the stable operation of removing residual monomer equipment generally.
(5) eliminate or reduced many factors, the PVC slurries overflow that causes as slurry bubble surpasses partition wall, condenser stops up and include coloured particles; And owing to remove the fluctuation transmission that the pressure and temperature imbalance causes in the residual monomer equipment, all of these factors taken together all influences the quality of PVC and the maintenance of equipment unfriendly.Thereby, more stable, the PVC of good quality more can be provided.In addition, improve the required step of maintenance facilities and loss of time of following to strengthen throughput.
Table 1
* used slurries: [a]=PVC: the homopolymer of the polymerization degree 1,300;
| Embodiment 123 | Comparative Examples 1234 | ||||||
| The coloured PVC of VC concentration (ppb) the flavescence factor (Δ YI) among porosity (ml/g) the bubbling state column plate A column plate B operating condition discharge region PVC of used slurries PVC (/PVC100g) | [a] 0.322 B A highly stable 250 2.21 0 | [b] 0.231 B A highly stable 350 8.62 0 | [c] 0.409 B A highly stable 200 2.72 0 | [a] 0.322 B B stablizes 100 7.52 5 | [b] 0.231 B B stablizes 350 8.82 4 | [c] 0.409 D C unstable 80,000 9.64 25 | [d] 0.231 B B stablizes 80,000 2.98 6 |
Concentration of slurry: 30% (weight); Residual monomer concentration: 30,000ppm;
The porosity of PVC: 0.322ml/g.[a]=PVC: the homopolymer of the polymerization degree 700;
Concentration of slurry: 30% (weight); Residual monomer concentration: 25,000ppm;
The porosity of PVC: 0.231ml/g.[a]=PVC: the homopolymer of the polymerization degree 1,300;
Concentration of slurry: 30% (weight); Residual monomer concentration: 30,000ppm;
The porosity of PVC: 0.409ml/g.
Claims (8)
1. equipment of from the slurries that contain polyvinyl chloride that contain residual monomer, removing residual monomer, its improvement is that described equipment comprises:
One hollow circle tube tower;
Be placed on some column plates in the tower at vertical direction, each column plate has many perforation;
Several chambers, each chamber forms on as one of column plate of the bottom of this chamber;
Be located at the slurries inlet at least two chambers;
Be located at the descender between two adjacent column plates, this district makes slurries flow to the column plate of low chamber in succession downwards from the column plate of higher chamber;
Be located at the steam-in at the bottom of the tower; With
Be located at than the slurries outlet in the low chamber of the chamber that the slurries inlet is arranged,
Wherein there is column plate diameter in one of the chamber of slurries inlets to be respectively this 1.05-5 that column plate diameter in each chamber up and down of chamber of slurries inlet arranged of next-door neighbour doubly.
2. according to the equipment of claim 1, also comprise the hot water jet device, this device is positioned near at least one column plate.
3. according to the equipment of claim 1, wherein the diameter in each hole is the 0.5-5.0 millimeter.
4. according to the equipment of claim 1, wherein the ratio of perforated area and column plate area is 0.001-10% in each column plate.
5. method of removing residual monomer with the defined equipment of claim 1, this method may further comprise the steps:
Add the slurries that contain polyvinyl chloride by the slurries inlet;
Be blown into steam by the steam-in that is positioned at the bottom of the tower;
When slurries are downward through column plate, slurries are contacted with steam;
Thereby from slurries, separate residual monomer; With the gas that goes out to contain the residual monomer of telling from tower top discharge, and the slurries of therefrom removing from slurries outlet discharging residual monomer;
Wherein the step that adds the slurries that contain polyvinyl chloride is undertaken by following (1), (2) or (3):
(1) under the situation that residual monomer is difficult to remove from slurries, add slurries by entering the mouth with the slurries that are provided with in the chamber on the chamber of larger-diameter column plate,
(2) under the situation that residual monomer is easy to remove from slurries, add slurries by the slurries inlet that is provided with in the chamber of band than the major diameter column plate, or add slurries than the slurries inlet that is provided with in the chamber under the chamber of major diameter column plate by band, or
(3) have under the situation of high bubbling at slurries, add slurries by the slurries inlet that is provided with in the chamber with larger-diameter column plate.
6. according to the method for claim 5, wherein when the porosity of polyvinyl chloride in the slurries is not less than 0.300 milliliter/gram, adds slurries in the chamber that larger-diameter column plate is arranged or be arranged in chamber under this chamber.
7. according to the method for claim 5, wherein when the porosity of polyvinyl chloride in the slurries is not less than 0.350 milliliter/gram, the slurries adding is had in the chamber of larger-diameter column plate.
8. according to the method for claim 5, wherein, slurries are added the chamber that is arranged on the chamber that larger-diameter column plate is arranged when the porosity of polyvinyl chloride in the slurries during less than 0.300 milliliter/gram.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP200038/1995 | 1995-08-04 | ||
| JP20003895A JP3724012B2 (en) | 1995-08-04 | 1995-08-04 | Residual monomer removal apparatus and residual monomer removal method using the same |
| JP200038/95 | 1995-08-04 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1150593A true CN1150593A (en) | 1997-05-28 |
| CN1073574C CN1073574C (en) | 2001-10-24 |
Family
ID=16417800
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN96112280A Expired - Fee Related CN1073574C (en) | 1995-08-04 | 1996-08-02 | Apparatus and method for removing residual monomers |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US5804039A (en) |
| EP (1) | EP0756883B1 (en) |
| JP (1) | JP3724012B2 (en) |
| KR (1) | KR100449195B1 (en) |
| CN (1) | CN1073574C (en) |
| CA (1) | CA2182068A1 (en) |
| DE (1) | DE69616683T2 (en) |
| MY (1) | MY114562A (en) |
| TW (1) | TW304964B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106414517A (en) * | 2014-05-28 | 2017-02-15 | 株式会社Lg化学 | Stripping apparatus |
| CN110354523A (en) * | 2019-07-14 | 2019-10-22 | 河北龙亿环境工程有限公司 | A kind of New Type of Tray with more microporous bubble covers |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3978797B2 (en) * | 1996-12-26 | 2007-09-19 | チッソ株式会社 | Residual monomer removal method and apparatus |
| WO2000064950A1 (en) * | 1999-04-22 | 2000-11-02 | Chisso Corporation | Device and method for removing unreacted monomer from polymer latex |
| FR2805757B1 (en) * | 2000-03-02 | 2002-05-31 | Solvay | METHOD AND INSTALLATION FOR EXTRACTING A MONOMER FROM AN AQUEOUS FOUL CONTAINING A POLYMER |
| US6830607B2 (en) * | 2001-06-15 | 2004-12-14 | Westlake Technology Corporation | Slurry tray and slurry tray assembly for use in fractionation towers |
| EP2370478B1 (en) * | 2008-12-30 | 2015-01-14 | Basell Poliolefine Italia S.r.l. | Steaming of polymer particles |
| WO2011114585A1 (en) | 2010-03-18 | 2011-09-22 | 電気化学工業株式会社 | Residual monomer elimination device and polyvinyl alcohol resin production method |
| CN103331030B (en) * | 2013-07-23 | 2015-08-05 | 新疆中泰化学股份有限公司 | Double overflow weir plate stripper configuration |
| CN105521628A (en) * | 2016-01-07 | 2016-04-27 | 永胜机械工业（昆山）有限公司 | Removing tower used in polyvinyl chloride resin production |
| JP7497157B2 (en) * | 2017-01-11 | 2024-06-10 | コーク－グリッシュ，リミティド パートナーシップ | Contact tray with baffle walls for concentrating low-flow liquids and method therewith - Patents.com |
| TW202012461A (en) * | 2018-06-07 | 2020-04-01 | 日商捷恩智股份有限公司 | Device for residual-monomer removal |
| WO2021150509A1 (en) * | 2020-01-21 | 2021-07-29 | Exxonmobil Chemical Patents Inc. | Strand evaporator used for devolatilizing polymers |
| JP6989800B2 (en) * | 2020-03-06 | 2022-01-12 | ダイキン工業株式会社 | Dispersion |
| US20230022810A1 (en) * | 2020-09-25 | 2023-01-26 | Lg Chem, Ltd. | Method for preparing vinyl chloride-based polymer |
Family Cites Families (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4017355A (en) * | 1970-12-18 | 1977-04-12 | Nippon Oil Company Ltd. | Process for treating latices |
| US4158092A (en) * | 1974-07-25 | 1979-06-12 | Hoechst Aktiengesellschaft | Process for the manufacture of vinyl chloride polymer dispersions with a low monomer content |
| US4184924A (en) * | 1974-08-19 | 1980-01-22 | Ethyl Corporation | Apparatus for steam stripping polyvinyl chloride resins |
| NO752264L (en) * | 1974-08-29 | 1976-03-02 | Huels Chemische Werke Ag | |
| DE2509937C3 (en) * | 1975-03-07 | 1981-04-16 | Hoechst Ag, 6000 Frankfurt | Device for the aftertreatment of homo- and copolymers of vinyl chloride |
| JPS5813563B2 (en) * | 1976-04-03 | 1983-03-14 | 信越化学工業株式会社 | Method and apparatus for removing unreacted monomers from an aqueous dispersion of vinyl chloride |
| JPS548693A (en) * | 1977-06-21 | 1979-01-23 | Chisso Corp | Removal of monomer from vinyl chloride resin slurry by steam treatment using improved plate column |
| US4303479A (en) * | 1977-10-07 | 1981-12-01 | The Goodyear Tire & Rubber Company | Distillation separation method |
| US4147859A (en) * | 1977-10-11 | 1979-04-03 | The B. F. Goodrich Company | Process for removal of chloroform and carbon tetrachloride from chlorinated polyvinyl chloride |
| DE2759097A1 (en) * | 1977-12-30 | 1979-07-12 | Norsk Hydro As | METHOD FOR REMOVING VINYL CHLORIDE FROM POLYVINYL CHLORIDE DISPERSIONS AND A COLUMN FOR CARRYING OUT THE METHOD |
| US4228273A (en) * | 1978-09-05 | 1980-10-14 | Tenneco Chemicals, Inc. | Process for the removal of vinyl chloride from aqueous dispersions of vinyl chloride resins |
| DE2903586A1 (en) * | 1979-01-31 | 1980-08-14 | Hoechst Ag | METHOD FOR THE CONTINUOUS REMOVAL OF RESIDUAL HYDROCARBONS FROM POLYOLEFINS AND DEVICE FOR CARRYING OUT THE METHOD |
| JPS5622305A (en) * | 1979-08-01 | 1981-03-02 | Chisso Corp | Monomer removal from vinyl chloride resin slurry by steaming and apparatus therefor |
| US4408040A (en) * | 1981-05-12 | 1983-10-04 | General Electric Company | Slurry granulation-steam stripping process for solvent removal |
| DE3200413A1 (en) * | 1982-01-09 | 1983-07-21 | Bayer Ag, 5090 Leverkusen | METHOD FOR DEMONOMERIZING POLYMER SLURRIES |
| JPH06827B2 (en) * | 1985-04-01 | 1994-01-05 | 三井東圧化学株式会社 | Continuous treatment method for polymerization reaction mixture |
| JP3029075B2 (en) * | 1992-09-25 | 2000-04-04 | チッソ株式会社 | Method and apparatus for producing resin powder with low residual vinyl monomer content by steam treatment of vinyl chloride resin slurry |
| JP3709568B2 (en) * | 1994-02-07 | 2005-10-26 | チッソ株式会社 | Residual monomer removal treatment method and residual monomer removal treatment tower used therefor |
| KR102030153B1 (en) * | 2017-12-15 | 2019-10-08 | 주식회사 포스코 | Ferritic stainless steel excellent in corrosion resistance and the manufacturing method for improving pickling property |
-
1995
- 1995-08-04 JP JP20003895A patent/JP3724012B2/en not_active Expired - Lifetime
- 1995-08-24 TW TW084108825A patent/TW304964B/zh active
-
1996
- 1996-07-25 CA CA002182068A patent/CA2182068A1/en not_active Abandoned
- 1996-07-31 US US08/690,143 patent/US5804039A/en not_active Expired - Fee Related
- 1996-08-01 EP EP96305693A patent/EP0756883B1/en not_active Expired - Lifetime
- 1996-08-01 DE DE69616683T patent/DE69616683T2/en not_active Expired - Fee Related
- 1996-08-02 CN CN96112280A patent/CN1073574C/en not_active Expired - Fee Related
- 1996-08-02 KR KR1019960032292A patent/KR100449195B1/en not_active IP Right Cessation
- 1996-08-03 MY MYPI96003188A patent/MY114562A/en unknown
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106414517A (en) * | 2014-05-28 | 2017-02-15 | 株式会社Lg化学 | Stripping apparatus |
| CN106414517B (en) * | 2014-05-28 | 2019-08-09 | 株式会社Lg化学 | Stripping apparatus |
| CN110354523A (en) * | 2019-07-14 | 2019-10-22 | 河北龙亿环境工程有限公司 | A kind of New Type of Tray with more microporous bubble covers |
| CN110354523B (en) * | 2019-07-14 | 2024-02-06 | 河北龙亿环境工程有限公司 | Novel column plate with microporous bubble cap |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0756883B1 (en) | 2001-11-07 |
| JP3724012B2 (en) | 2005-12-07 |
| EP0756883A2 (en) | 1997-02-05 |
| US5804039A (en) | 1998-09-08 |
| JPH0948815A (en) | 1997-02-18 |
| TW304964B (en) | 1997-05-11 |
| KR100449195B1 (en) | 2004-12-03 |
| KR970010799A (en) | 1997-03-27 |
| CN1073574C (en) | 2001-10-24 |
| MY114562A (en) | 2002-11-30 |
| CA2182068A1 (en) | 1997-02-05 |
| EP0756883A3 (en) | 1997-08-27 |
| DE69616683T2 (en) | 2002-08-01 |
| DE69616683D1 (en) | 2001-12-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1073574C (en) | Apparatus and method for removing residual monomers | |
| CN1260197C (en) | Method for distilling (meth)acrylic acid | |
| CN1114621C (en) | Process for continuous polymerization with micromixing of reactive fluids | |
| CN1080580C (en) | Distributor allowing independent injection and/or removal of fluids | |
| CN1317254C (en) | (meth)acrylic acid crystal and method for the production and purification of aqueous (meth)acrylic acid | |
| CN1161329C (en) | Improved method for neutralizing organic acid | |
| CN1195172C (en) | Combustion process and apparatus therefor containing separate injection of fuel and oxidant streams | |
| CN1823032A (en) | Thermal separating method for separating at least one mass flux containing enriched (meth)acrylic monomers | |
| CN1703390A (en) | Preparation of acrylic acid | |
| CN1275180A (en) | Cleaning water discharge apparatus | |
| CN1617843A (en) | Method for vapor phase catalytic oxidation | |
| CN1255487A (en) | Method and appts. for preparing esterification products | |
| CN1678715A (en) | Two stage hydrocarbon conversion reaction system | |
| CN1136037C (en) | Process for effecting mass transfer between liquid phase and gaseous phase | |
| CN1086306C (en) | Method for treating fume and system thereof | |
| CN1092078A (en) | Polymer finishing process | |
| CN1130651A (en) | Organic polymer-calcium carbonate composite particles, hollow calcium carbonate particles, processes for their preparation, their use | |
| CN1013201B (en) | Processes of bulk polymerization for preparing polymers or copolymers based on chloro ethelene | |
| CN1180865C (en) | Distillation appts. and distillation process | |
| CN1226181A (en) | Column and process for deodorising dispersions | |
| CN1137149C (en) | Device and method for removing unreacted monomer from polymer latex | |
| CN1050722A (en) | The polymerization unit and the method for preparation vinyl chloride resin | |
| CN1198850C (en) | Process for continuous production of gel free polymers, and powder and liquid coating applications contg. gel free polymers | |
| CN1011861B (en) | Improvements in fluidized-bed polymerization reactor | |
| CN1717269A (en) | Method and device for hydrolytically obtaining a carboxylic acid and alcohol from the corresponding carboxylic ester |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |